NASSA. 349 



1844; and he has given us some amusing particulars of 

 the fry. These behaved themselves like the fry of other 

 Gastropods, skipping about and whirling round by means 

 of their ciliated lobes, apparently in a state of pleasur- 

 able excitement ; but it seems that the exercise was 

 compulsory, or necessary to prevent the attacks of a 

 swarm of Infusoria, which made short work of any tired 

 or feeble infant Nassa. The shell varies considerably 

 in size and in the length of the spire ; an adult speci- 

 men, from Mr. Clark's collection, is not half an inch 

 long. 



Linne gave the Mediterranean as "the only locality 

 known to him. The present species is the Buccinum 

 cancellatum &c. of Lister, B. vulgatum of Gmelin, and 

 probably the B. tessulatum of Olivi ; B. reticulatum of 

 the last-named author may be the next species. The 

 young appears to be the B. pullus of Pennant but not of 

 Linne. 



2. N. ni'tida*, Jeffreys. 



Body greyish, with a slight tinge of purple, and closely 

 speckled with flake-white : pallia! tube cylindrical, very long, 

 slender, , and flexible : tentacles flattened, tapering to a fine 

 point : eyes small, on stalks conjoined with the tentacles on 

 their outside ; these stalks are about half the length of the 

 tentacles, so that the eyes are placed about the middle of the 

 latter : foot broadly lanceolate, squarish and double-edged in 

 front, with small and pointed corners, blunt and wedge-shaped 

 behind ; tail forked and ridged : appendages rather short and 

 yellowish. 



Shell differing from N. reticulata in the following particu- 

 lars : — It is smaller, narrower, and remarkably glossy ; the ribs 

 are much fewer, viz. 10 to 12 on the body- whorl, 15 on 

 the next, 16 or 17 on the next, and 18 on the next whorl, 

 when they diminish in number upwards ; occasionally the ribs 

 are varicose ; the spiral striae or ridges are also less numerous, 



* Glossy. 



